1. Field of the Invention
The present invention relates to cartridge for the expulsion of liquids under pressure, including a chamber for a propellent charge and a separating arrangement which is located intermediate the chamber for the propellent charge and a liquid chamber.
A cartridge of this type serves for utilization in a so-called hydraulic or water hammer, which represents a cannon-like apparatus. Through the intermediary of such water hammers, water columns are fixed in order to be able to loosen vestigial rock or stone cores; for example, for underground or mining tunneling or gallery construction. Hereby, it is of particular advantage, that for this apparatus there can be avoided the ordinarily usual dangerous formation of sparks, as well as an uncontrolled flying around of stone or rock fragments during blasting.
The utilization of this water hammer in a driving gallery is hereby undertaken in such a manner that with the aid of a gallery or tunneling-profile cutting machine, by means of high-pressure water there is initially cut out a semicircularly-shaped driving gallery section of about 0.5 m to 1 m at its edge. Hereby, the gallery or tunnel core remains intact. Into this core there are then drilled holes in a precalculated arrangement or pattern. The comminuting of the core of the gallery there is now carried out with the water hammer, for which purpose water is fired at a high velocity of about 1,000 m/s into the drilled hole. Hereby, pressures in the magnitude of a few thousand bar are produced in the drilled hole. Through this pressure impact there is then comminuted the stone or rock.
2. Discussion of the Prior Art
From the disclosure of German Patent No. 35 45 737 there has already become known a cartridge for the expulsion of liquids, especially of water, under pressure.
This prior art cartridge possesses a cylindrical liquid chamber and a chamber for a propellent charge which is located ahead of this liquid chamber and is separated therefrom by means of a separating arrangement. In this instance, the separating arrangement is formed as a piston with a hollow space, which piston contacts the inner wall surface of the chambers, and wherein the end surface of the piston which faces towards the liquid chamber possesses at least one breaking location. The tip of the cartridge is configured in a nozzle-shape. This cartridge which is constituted from the propellent charge chamber, the separating element and the liquid chamber is inserted into a firing installation in readiness for firing; in essence, equipped, on the one hand, with the propellent charge and, on the other hand, with the liquid. Hereby, it is considered as being disadvantageous that the liquid is contained in the liquid chamber and, as a consequence thereof, special measures are necessary in order to avoid the egress of liquid. In addition thereto, there must also be taken into account the not quite insignificant increase in the weight of such a cartridge.